US4741213A - Quartz-type gas pressure gauge - Google Patents
Quartz-type gas pressure gauge Download PDFInfo
- Publication number
- US4741213A US4741213A US07/012,355 US1235587A US4741213A US 4741213 A US4741213 A US 4741213A US 1235587 A US1235587 A US 1235587A US 4741213 A US4741213 A US 4741213A
- Authority
- US
- United States
- Prior art keywords
- quartz
- quartz vibrator
- resonance
- pressure
- gas pressure
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 239000010453 quartz Substances 0.000 claims abstract description 44
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N silicon dioxide Inorganic materials O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims abstract description 44
- 239000013078 crystal Substances 0.000 abstract description 6
- 238000005259 measurement Methods 0.000 abstract description 5
- 238000010586 diagram Methods 0.000 description 7
- 230000007423 decrease Effects 0.000 description 5
- 230000010355 oscillation Effects 0.000 description 2
- 230000003321 amplification Effects 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L9/00—Measuring steady of quasi-steady pressure of fluid or fluent solid material by electric or magnetic pressure-sensitive elements; Transmitting or indicating the displacement of mechanical pressure-sensitive elements, used to measure the steady or quasi-steady pressure of a fluid or fluent solid material, by electric or magnetic means
- G01L9/0001—Transmitting or indicating the displacement of elastically deformable gauges by electric, electro-mechanical, magnetic or electro-magnetic means
- G01L9/0008—Transmitting or indicating the displacement of elastically deformable gauges by electric, electro-mechanical, magnetic or electro-magnetic means using vibrations
- G01L9/0022—Transmitting or indicating the displacement of elastically deformable gauges by electric, electro-mechanical, magnetic or electro-magnetic means using vibrations of a piezoelectric element
Definitions
- the present invention relates to a gas pressure gauge which measures the pressure of a gas by using a quartz vibrator.
- a quartz-type gas pressure gauge has heretofore been known in which a single sensor is capable of measuring the gas pressure of from atmospheric pressure through up to 10 -3 Torr. That is, since it was found that resonance resistance of a quartz vibrator exhibits dependency upon the pressure of ambient atmosphere over a wide range, gas pressure gauges have been developed in which a single sensor measures the pressure of from atmospheric pressure through up to 10 -3 Torr by utilizing the above-mentioned phenomenon. This has been disclosed in, for example, "Keiso" (Development of a very small Vacuum Sensor using a Quartz Vibrator), Vol. 27, No. 7, 1984.
- the resonance resistance of quartz vibrator greatly changes in a low pressure region of 10 -3 to about 10 -2 Torr, making it difficult to take measurement maintaining precision.
- FIG. 4 illustrates temperature characteristics of resonance resistance of a conventional quartz vibrator.
- the resonance resistance greatly changes with the change in the temperature, i.e., the resonance resistance increases with the increase in the temperature.
- the resonance resistance is mostly affected by friction with the air, and does not greatly change even when the temperature is changed. According to the conventional technique, therefore, the resonance resistance is seriously affected by the temperature as the gas pressure decreases, and error develops in the measurement.
- FIG. 1 is a block diagram of a circuit of a quartz-type gas pressure gauge
- FIG. 2 is a diagram showing gas pressure vs. resonance resistance, resonance current characteristics of a quartz vibrator
- FIG. 3 is a diagram showing meter drive voltage vs. gas pressure characteristics
- FIG. 4 is a diagram of temperature characteristics of resonance resistance of a conventional quartz vibrator
- FIG. 5 is a perspective view of a tuning fork-type quartz vibrator
- FIG. 6 is a diagram of resonance resistance vs. temperature characteristics of tuning fork-type quartz vibrators with cutting angles as parameters.
- the present invention is concerned with a quartz-type gas pressure gauge which utilizes the fact that the quartz vibrator exhibits resonance resistance that changes depending upon the pressure of ambient gas under the condition where the quartz vibrator is stably vibrated at resonance frequency in a phase locked loop circuit (hereinafter referred to as PLL circuit), the quartz vibrator being of the type of a tuning fork obtained from a Z-plate of quartz crystal and being cut at an angle of greater than 1°50' with respect to the Y-axis.
- PLL circuit phase locked loop circuit
- the quartz vibrator of the type of tuning fork obtained from a Z-plate of quartz crystal which is cut at an angle of greater 1°50' with respect to the Y-axis, exhibits parabolic temperature-resonance resistance characteristics, the peak thereof lying near ordinary temperature at which the gauge is used and the parabola opening broadly. Therefore, the temperature-resonance resistance characteristics are nearly flat in the temperature regions where the gauge is used, and are not much affected by the change in the ambient temperature. (Embodiment)
- FIG. 2 is a diagram illustrating a relationship between the pressure of a gas and the resonance resistance and the resonance current of a quartz vibrator according to the present invention.
- the quartz vibrator exhibits resonance resistance from the atmospheric pressure through up to 10 -3 Torr. If this quartz vibrator is driven at a constant voltage, there is obtained a resonance current - gas pressure curve that is represented by i in FIG. 2.
- the resonance current exhibits sensitivity for the gas pressure from the atmospheric pressure through up to 10 -3 Torr. From the standpoint of easily taking measurement, therefore, it is better to measure the resonance current or the resonance voltage than to measure the resonance resistance.
- FIG. 1 is a block diagram of a circuit of a quartz-type gas pressure gauge contemplated by the present invention.
- the pressure gauge consists of a PLL circuit 11, a display converter circuit 12, and a display unit 13.
- the PLL circuit 11 consists of a frequency variable oscillator 1 which is controlled by a current or a voltage, an amplifier 2 which performs the amplification with the resonance current of the quartz vibrator 5 as a voltage, a phase comparator 3 which compares the phase of an output signal of the amplifier 2 with the phase of an output signal of the frequency variable oscillator 1, and a low-pass filter 4 which converts pulse-like output signals of the phase comparator 3 into a d-c voltage.
- the output voltage of the low-pass filter 4 controls the oscillation frequency of the frequency variable oscillator 1.
- the quartz vibrator 5 which is a pressure sensor is connected to the output terminal of the frequency variable oscillator 1 and to the input terminal of the amplifier 2.
- the oscillation frequency of the frequency variable oscillator 1 has been controlled at all times so that the phase difference becomes zero between the output signal of the frequency variable oscillator 1, i.e., the drive voltage of the quartz vibrator 5 and the output signal of the amplifier 2, i.e., the current that flows through the quartz vibrator 5. That is, the quartz vibrator 5 is driven at its own resonance frequency at all times, presenting a significant meaning from the standpoint of putting the quartz-type gas pressure gauge into practice. This is because, the resonance frequency of the quartz vibrator is subject to change depending upon the pressure of the surrounding gas.
- the display converter circuit 11 consists of a main amplifier 6 which further amplifies the signal of the amplifier 2, a rectifier 7 which rectifies the output signals of the main amplifier 6 into a direct current, an inverter 8 which inverts the polarity of output voltage of the rectifier 7, and a buffer 9 which applies a bias to the output voltage of the inverter 8.
- the amount of bias can be arbitrarily changed by a variable resistor 9a.
- the display unit 13 displays the pressure of a gas in a digital or in an analog manner, and is comprised of a meter 10 in this embodiment, so that the pressure of gas can be read from the deflecting angle of the meter 10.
- the pressure characteristics of resonance current of the quartz vibrator are shown in FIG. 2; i.e., the resonance current increases with the decrease in the pressure of ambient gas. Therefore, if the resonance current is amplified as a voltage and is rectified into a direct current to drive the meter 10, the deflecting angle of the meter 10 increases with the decrease in the pressure to make an indication that is contrary to common sense.
- a meter drive voltage shown in FIG. 3 can be obtained by inverting the polarity of the d-c voltage by the inverter 8 and by applying a bias voltage by the buffer 9. In the example of FIG. 3, the amount of bias is so adjusted that the meter drive voltage will be 10 volts under atmospheric pressure.
- ordinary pressure indication can be obtained in which the needle of the meter is perfectly deflected under the atmospheric pressure, and the deflecting angle of the meter decreases with the decrease in the pressure.
- FIG. 5 is a perspective view of a quartz vibrator 5 employed in the present invention.
- the quartz vibrator 5 is of the type of a tuning fork which consists of two arms and a leg 15 which supports them. On the surface are arranged a pair of electrodes (Au/Cr double-layer structure) 16.
- the PLL circuit 11 is connected to both ends of the electrodes.
- Arms of the tuning fork may have a length L of 10 mm, a width T of 3.25 mm and a thickness W of 130 ⁇ . The sizes, however, need not be limited to these values only.
- the Z-axis is an optical axis that passes through a vertex of the quartz crystal.
- the X-axis exists on a plane perpendicular to the Z-axis, and extends toward a vertex of the hexagonal pole of quartz crystal. Therefore, there are three X-axes that are separated apart by 120°.
- the Y-axis is on a plane perpendicular to the Z-axis, and intersects the X-axis at right angles.
- the angle of cutting the tuning fork-type quartz vibrator i.e., the azimuth of cutting the crystal
- the tuning fork is cut out from a flat plate (i.e., Z-plane) that is defined by the X-axis and by the Y'-axis which is given by turning the Y-axis in the counterclockwise direction by ⁇ with the X-axis as an axis of rotation.
- FIG. 6 illustrates temperature - resonance resistance characteristics of tuning fork-type quartz vibrators that are cut at some different angles ⁇ under low-pressure conditions.
- the resonance resistance of ordinate is a relative memory of when a peak value is set at 100.
- a peak value of parabola is exhibited at 15° C., the parabola opening in a small amount. Therefore, flat characteristics are not exhibited near ordinary temperature (25° C.) which lies in a range where the pressure gauge is used.
- the peak value shifts to near 30° C. which approaches normal temperature of a range where the pressure gauge is used.
- the gas pressure gauge which utilizes the resonance resistance of a quartz vibrator that changes depending upon the pressure of the surrounding gas of the present invention, use is made of a tuning fork-type quartz vibrator that is cut at an angle of greater then 1°50'. Namely, there is obtained a gas pressure gauge of which the resonance resistance varies little depending upon the temperature under low pressure conditions, making it possible to obtain measurement maintaining increased precision under low-pressure conditions.
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Measuring Fluid Pressure (AREA)
- Piezo-Electric Or Mechanical Vibrators, Or Delay Or Filter Circuits (AREA)
- Oscillators With Electromechanical Resonators (AREA)
Abstract
Description
Claims (1)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP61025392A JPS62184325A (en) | 1986-02-07 | 1986-02-07 | Quartz type gas pressure gauge |
JP61-25392 | 1986-02-07 |
Publications (1)
Publication Number | Publication Date |
---|---|
US4741213A true US4741213A (en) | 1988-05-03 |
Family
ID=12164612
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US07/012,355 Expired - Lifetime US4741213A (en) | 1986-02-07 | 1987-02-09 | Quartz-type gas pressure gauge |
Country Status (3)
Country | Link |
---|---|
US (1) | US4741213A (en) |
EP (1) | EP0233054A3 (en) |
JP (1) | JPS62184325A (en) |
Cited By (25)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4960000A (en) * | 1988-11-02 | 1990-10-02 | Asulab, S.A. | Device for measuring a physical quantity |
US4995265A (en) * | 1989-01-23 | 1991-02-26 | Balzers Aktiengesellschaft | Degradation and contamination compensated tuning fork quartz monometer, and method to compensate for tuning quartz degradation and contamination |
US5033306A (en) * | 1988-06-13 | 1991-07-23 | Seiko Electronic Components Ltd. | Quartz vacuum gauge |
US5221873A (en) * | 1992-01-21 | 1993-06-22 | Halliburton Services | Pressure transducer with quartz crystal of singly rotated cut for increased pressure and temperature operating range |
US5319965A (en) * | 1992-03-02 | 1994-06-14 | Halliburton Company | Multiple channel pressure recorder |
DE19504218A1 (en) * | 1995-02-09 | 1995-12-21 | Telefunken Microelectron | Measuring or monitoring pressure inside pressure container |
DE19627878C1 (en) * | 1996-07-11 | 1997-10-02 | Temic Bayern Chem Airbag Gmbh | Gas generator for vehicle air-bag system |
WO2001075410A1 (en) * | 2000-03-30 | 2001-10-11 | Halliburton Energy Services | Quartz pressure transducer containing microelectronics |
US20080185142A1 (en) * | 2007-02-07 | 2008-08-07 | Halliburton Energy Services, Inc. | Downhole transducer with adjacent heater |
US20100132471A1 (en) * | 2008-12-03 | 2010-06-03 | Hedtke Robert C | Method and apparatus for pressure measurement using quartz crystal |
US20100154553A1 (en) * | 2007-06-04 | 2010-06-24 | Nxp B.V. | Pressure gauge |
US20110072886A1 (en) * | 2009-09-30 | 2011-03-31 | Catherine Genevieve Caneau | Gas Sensor Based On Photoacoustic Detection |
US7954383B2 (en) | 2008-12-03 | 2011-06-07 | Rosemount Inc. | Method and apparatus for pressure measurement using fill tube |
US8132464B2 (en) | 2010-07-12 | 2012-03-13 | Rosemount Inc. | Differential pressure transmitter with complimentary dual absolute pressure sensors |
US8327713B2 (en) | 2008-12-03 | 2012-12-11 | Rosemount Inc. | Method and apparatus for pressure measurement using magnetic property |
US20130333774A1 (en) * | 2010-11-29 | 2013-12-19 | Air Products And Chemicals, Inc. | Method of and apparatus for measuring the pressure of a gas |
US8752433B2 (en) | 2012-06-19 | 2014-06-17 | Rosemount Inc. | Differential pressure transmitter with pressure sensor |
US9441997B2 (en) | 2012-05-24 | 2016-09-13 | Air Products And Chemicals, Inc. | Method of, and apparatus for, measuring the physical properties of two-phase fluids |
US9448094B2 (en) | 2010-11-29 | 2016-09-20 | Air Products And Chemicals, Inc. | Method of and apparatus for measuring the mass flow rate of a gas |
US9448090B2 (en) | 2012-05-24 | 2016-09-20 | Air Products And Chemicals, Inc. | Method of, and apparatus for, measuring the mass flow rate of a gas |
US9459191B2 (en) | 2010-11-29 | 2016-10-04 | Air Products And Chemicals, Inc. | Method of and apparatus for measuring the molecular weight of a gas |
US9581297B2 (en) | 2012-05-24 | 2017-02-28 | Air Products And Chemicals, Inc. | Method of, and apparatus for, measuring the true contents of a cylinder of gas under pressure |
US9690304B2 (en) | 2012-05-24 | 2017-06-27 | Air Products And Chemicals, Inc. | Method of, and apparatus for, providing a gas mixture |
US9804010B2 (en) | 2012-05-24 | 2017-10-31 | Air Products And Chemicals, Inc. | Method of, and apparatus for, regulating the mass flow rate of a gas |
US9870007B2 (en) | 2012-05-24 | 2018-01-16 | Air Products And Chemicals, Inc. | Method of, and apparatus for, providing a gas mixture |
Families Citing this family (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0379841B2 (en) * | 1989-01-23 | 1998-11-04 | Balzers Aktiengesellschaft | Gas pressure measuring apparatus |
CH687276A5 (en) * | 1989-01-23 | 1996-10-31 | Balzers Hochvakuum | Tuning fork quartz manometer. |
JP2764754B2 (en) * | 1989-12-20 | 1998-06-11 | セイコーインスツルメンツ株式会社 | Pressure detector using crystal oscillator |
DE4004969A1 (en) * | 1990-02-19 | 1991-08-22 | Asea Brown Boveri | Quartz oscillator mechanical resonant frequency measuring CCT - contains bridge circuit in PLL feedback loop and potentiometer set to null |
JP4794185B2 (en) * | 2005-03-10 | 2011-10-19 | シチズンファインテックミヨタ株式会社 | Pressure sensor |
RU2627544C2 (en) * | 2015-09-30 | 2017-08-08 | Валерий Владимирович Коваленко | Piezo resonant-viscous vacuum gauge |
RU175121U1 (en) * | 2016-06-08 | 2017-11-21 | Юлия Александровна Солдатова | PRIMARY CONVERTER OF A PIEZER RESONANT VISCOUS VACUUM METER |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4638664A (en) * | 1984-10-03 | 1987-01-27 | Seiko Instruments & Electronics Ltd. | Quartz barometer |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2529670A1 (en) * | 1982-07-01 | 1984-01-06 | Asulab Sa | SENSITIVE ELEMENT FOR CONSTRAINTS SENSOR AND SENSOR BY APPLYING |
FR2532047A1 (en) * | 1982-08-19 | 1984-02-24 | Asulab Sa | MEASURING SENSOR PROVIDED WITH A PIEZOELECTRIC RESONATOR COMPENSATED IN TEMPERATURE |
JPS6110735A (en) * | 1984-06-25 | 1986-01-18 | Seiko Instr & Electronics Ltd | Gas pressure gage |
-
1986
- 1986-02-07 JP JP61025392A patent/JPS62184325A/en active Pending
-
1987
- 1987-02-04 EP EP87301000A patent/EP0233054A3/en not_active Withdrawn
- 1987-02-09 US US07/012,355 patent/US4741213A/en not_active Expired - Lifetime
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4638664A (en) * | 1984-10-03 | 1987-01-27 | Seiko Instruments & Electronics Ltd. | Quartz barometer |
Cited By (31)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5033306A (en) * | 1988-06-13 | 1991-07-23 | Seiko Electronic Components Ltd. | Quartz vacuum gauge |
US4960000A (en) * | 1988-11-02 | 1990-10-02 | Asulab, S.A. | Device for measuring a physical quantity |
US4995265A (en) * | 1989-01-23 | 1991-02-26 | Balzers Aktiengesellschaft | Degradation and contamination compensated tuning fork quartz monometer, and method to compensate for tuning quartz degradation and contamination |
US5221873A (en) * | 1992-01-21 | 1993-06-22 | Halliburton Services | Pressure transducer with quartz crystal of singly rotated cut for increased pressure and temperature operating range |
US5319965A (en) * | 1992-03-02 | 1994-06-14 | Halliburton Company | Multiple channel pressure recorder |
DE19504218A1 (en) * | 1995-02-09 | 1995-12-21 | Telefunken Microelectron | Measuring or monitoring pressure inside pressure container |
DE19627878C1 (en) * | 1996-07-11 | 1997-10-02 | Temic Bayern Chem Airbag Gmbh | Gas generator for vehicle air-bag system |
WO2001075410A1 (en) * | 2000-03-30 | 2001-10-11 | Halliburton Energy Services | Quartz pressure transducer containing microelectronics |
US6598481B1 (en) * | 2000-03-30 | 2003-07-29 | Halliburton Energy Services, Inc. | Quartz pressure transducer containing microelectronics |
US20080185142A1 (en) * | 2007-02-07 | 2008-08-07 | Halliburton Energy Services, Inc. | Downhole transducer with adjacent heater |
US7784350B2 (en) | 2007-02-07 | 2010-08-31 | Halliburton Energy Services, Inc. | Downhole transducer with adjacent heater |
US8627726B2 (en) * | 2007-06-04 | 2014-01-14 | Nxp, B.V. | Pressure gauge |
US20100154553A1 (en) * | 2007-06-04 | 2010-06-24 | Nxp B.V. | Pressure gauge |
US7870791B2 (en) | 2008-12-03 | 2011-01-18 | Rosemount Inc. | Method and apparatus for pressure measurement using quartz crystal |
US20100132471A1 (en) * | 2008-12-03 | 2010-06-03 | Hedtke Robert C | Method and apparatus for pressure measurement using quartz crystal |
US7954383B2 (en) | 2008-12-03 | 2011-06-07 | Rosemount Inc. | Method and apparatus for pressure measurement using fill tube |
US8327713B2 (en) | 2008-12-03 | 2012-12-11 | Rosemount Inc. | Method and apparatus for pressure measurement using magnetic property |
WO2010065282A1 (en) * | 2008-12-03 | 2010-06-10 | Rosemount Inc. | Method and apparatus for pressure measurement using quartz crystal |
US20110072886A1 (en) * | 2009-09-30 | 2011-03-31 | Catherine Genevieve Caneau | Gas Sensor Based On Photoacoustic Detection |
US8132464B2 (en) | 2010-07-12 | 2012-03-13 | Rosemount Inc. | Differential pressure transmitter with complimentary dual absolute pressure sensors |
US9239271B2 (en) * | 2010-11-29 | 2016-01-19 | Air Products And Chemicals, Inc. | Method of and apparatus for measuring the pressure of a gas |
US20130333774A1 (en) * | 2010-11-29 | 2013-12-19 | Air Products And Chemicals, Inc. | Method of and apparatus for measuring the pressure of a gas |
US9448094B2 (en) | 2010-11-29 | 2016-09-20 | Air Products And Chemicals, Inc. | Method of and apparatus for measuring the mass flow rate of a gas |
US9459191B2 (en) | 2010-11-29 | 2016-10-04 | Air Products And Chemicals, Inc. | Method of and apparatus for measuring the molecular weight of a gas |
US9441997B2 (en) | 2012-05-24 | 2016-09-13 | Air Products And Chemicals, Inc. | Method of, and apparatus for, measuring the physical properties of two-phase fluids |
US9448090B2 (en) | 2012-05-24 | 2016-09-20 | Air Products And Chemicals, Inc. | Method of, and apparatus for, measuring the mass flow rate of a gas |
US9581297B2 (en) | 2012-05-24 | 2017-02-28 | Air Products And Chemicals, Inc. | Method of, and apparatus for, measuring the true contents of a cylinder of gas under pressure |
US9690304B2 (en) | 2012-05-24 | 2017-06-27 | Air Products And Chemicals, Inc. | Method of, and apparatus for, providing a gas mixture |
US9804010B2 (en) | 2012-05-24 | 2017-10-31 | Air Products And Chemicals, Inc. | Method of, and apparatus for, regulating the mass flow rate of a gas |
US9870007B2 (en) | 2012-05-24 | 2018-01-16 | Air Products And Chemicals, Inc. | Method of, and apparatus for, providing a gas mixture |
US8752433B2 (en) | 2012-06-19 | 2014-06-17 | Rosemount Inc. | Differential pressure transmitter with pressure sensor |
Also Published As
Publication number | Publication date |
---|---|
EP0233054A2 (en) | 1987-08-19 |
JPS62184325A (en) | 1987-08-12 |
EP0233054A3 (en) | 1989-04-19 |
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